Although a tan has long been considered a symbol indicative of good health and the ability to secure sufficient leisure time to enjoy many and numerous outdoor activities, it has become very evident that excessive exposure of the human skin to sunlight is harmful.
It is well documented that human skin, and most likely most mammalian skin, is sensitive to sunlight and artificial light containing radiation of wavelengths between about 290 nanometers (nm) and 400 nm. Ultraviolet radiation of wavelengths between about 290 nm and 320 nm (UV-B region) has been known to rapidly produce damaging effects on the skin including reddening or erythema, edema, blistering or other skin eruptions in more severe cases. Prolonged or chronic exposure to radiation in this wavelength range has been associated with serious skin conditions such as actinic keratoses and carcinomas. In recent years, concern has also been expressed regarding ultraviolet radiation of wavelengths above 320 nm (UV-A region) and the adverse effects of such radiation on human skin. The radiation between 320 and 400 nm also contributes to the premature aging of the skin. In addition, recent studies indicate that chronic sun exposure limits the immuno-response of the skin. There is some evidence that a tan will offer some protection against burning but that the tan is quite ineffectual against many other types of solar damage and there is no evidence that a tan increases immuno-responsive function in human skin.
Growing public awareness that the enjoyment of outdoor activities includes the need for adequate sun protection has led to an unprecedented growth in the area of sunscreen products. A study by Margaret Schlumpf from the Institute of Pharmacology and Toxicology at the University of Zurich, supports earlier health concerns regarding the use of endocrine disrupting organic substances in nearly all UV screening chemicals used in sunscreens. Additionally, the use of aloe, or more specifically aloe barbadensis Miller has heretofore been known to be a useful agent for the formulation of sunscreens as well as a substance that can both reduce UV damage to human skin that is inflamed and also promote healing. What was not well documented until recent publications and a subsequent U.S. Pat. No. 5,824,659 by Strickland and coworkers is that an extract found in all Aloe plants that is normally removed during carbon adsorptive processing, is capable of providing cytoprotection to the mammalian skin. This extract boosts the immune system response of the skin, thereby significantly reducing the risk to various forms of skin cancer. There is strong evidence to suggest that this beneficial effect translates to skin in most mammals, thereby the present disclosure provides a possible preventative formulation for animals in zoos or other habitats where UV exposure could be hazardous to the animals' health.
It is therefore desirable to provide a UV protective product that has the following attributes: protection in the UV-A and UV-B long range and short range ultraviolet radiation ranges; maintenance of coverage, i.e., waterproof and perspiration proof; application and use convenience, i.e., ease of application, invisibility, non-staining and non-greasy; and freedom from irritation as a result of its ingredients, in particular, its active sun-block or sunscreen ingredients should also be void of any known or suspected endocrine disrupters. Recent interest in this area includes some concerns over the irritancy and sensitization problems in addition to the endocrine disruptive nature that may occur in some individuals utilizing sunscreen products with high SPF values containing organic sunscreen agents. In addition, the UV protective product could also include known cytoprotective oligosaccharides from aloe barbadensis Miller preventing damage to the skin immune system caused by harmful UV radiation. “Cold-pressed” Aloe which contains the beneficial oligosaccharides and provides an emollient base for the UV protective formulation is possibly the best known choice as a cytoprotective agent that inhibits the loss of skin immuno-competency induced by ultraviolet radiation, as this agent is readily available and comparably inexpensive. Other such inhibitors are not yet well known but it is believed that amino-acids, vitamins or pro-vitamins, nucleo-derivatives, and vegetable extracts, wherein said amino acids comprise tryptophan, histidine, phenylalanine, tyrosine, said vitamins and provitamins comprise vitamin B6, vitamin A, vitamin E, tocopherols and in particular D-alpha tocopherol, beta carotene, bioflavonoids, nucleotides and polymers thereof, cascara, frangula, camomile, hyperic, calendula, elicriso, licorice or essential oils thereof all may have similar cytoprotective or immune boosting effects on mammalian skin. The essential oils of frankincense and rosemary have been found to work effectively and synergistically in strengthening the neuromuscular response of patients who are exposed to its scent in combination with compositions of the present disclosure.
One current measure of effectiveness of a sun protective product is indicated by its sun protection factor (SPF). The sun protection factor is the ratio of the amount of exposure (dose) required to produce a minimal erythema reaction in protected skin to the amount required to produce the same reaction in unprotected skin. The absolute dose differs for each human and for each mammal, and is largely dependent on genetic predisposition and ethnic origin of the human. If a human or other mammal would normally require ten minute exposure to sunlight to develop a minimal erythema reaction, then using an SPF 15 sun-block should allow for tolerance of up to 150 minutes of sunlight before developing a minimal erythema. Relatively recent public awareness of the problems of exposure to sunlight has led to a demand for sun-block products with high SPF values, i.e., at or above SPF 8.
What has not been well considered in the sun protection and cosmetics industry heretofore, is the possibility of enhancing the immuno-responsiveness of skin cells to UV light by the proper topical application such as described above by the use of extracts of aloe or similar naturally occurring substances (including kukui nut extract for example or other similar anti-inflammatory naturally occurring substances). Such substances would preferably not be processed, but if the beneficial effects are not lost during processing, then either the processed or non-processed substance may be used. The importance of processing within a short time period after harvesting the aloe plant or other plants/nuts, etc. as well as keeping the plant and subsequent plant extract cool (at or below room temperature) during processing is now well understood. Essential oils including specifically frankincense and rosemary have been shown to possibly have immuno-enhancing properties, as determined by Kinesiologist Dr. John Schmidt of Triangle Wellness Center at 182 Wind Chime Ct. Ste. 203 Raleigh, N.C. 27615. This was determined by a strengthening in neuromuscular response using scent (aroma) testing of these essential oils. The testing was performed both together with compositions of the present disclosure and alone.
Our review of the art in this field includes the following pertinent information;
For example, Japanese Patent Application No. 1981-161, 881, describes cosmetics containing 0.1-40% of ultrafine divided titanium oxide with a particle size of 10-30 nm which has been rendered hydrophobic. It indicates that when hydrophobically treated titanium dioxide with a particle size of 10-30 nm is blended into cosmetic base materials, it transmits visible light but reflects and scatters the harmful ultraviolet rays. It has been found that when these titanium dioxide compositions are utilized as a sunscreen agent in sunscreen compositions, it may result in the loss of one of the most desired properties of such compositions, i.e., invisibility.
U.S. Pat. No. 5,028,417, issued Jul. 2, 1991, describes sunscreen compositions containing microfine titanium dioxide. The particle size of the titanium dioxide is required to be less than 10 nm. It also states that other sunscreen agent can be utilized with the titanium dioxide. U.S. Pat. No. 5,340,567, issued Aug. 23, 1994 describes a sunscreen composition comprising a synergistic combination of titanium dioxide having a particle size of less than about 35 nm and zinc oxide having a particle size of less than about 50 nm with titanium dioxide and zinc oxide being present at given ratios.
German Patent No. 3642794 (1987) describes a cosmetic composition for preventing sunburn which contains 1-25% zinc oxide of a particle size of 70-300 microns. It further indicates that the composition may also contain titanium dioxide of a particle size of 30-70 microns. This composition is undesirably due to its unaesthetic whiteness characteristics at high SPF levels.
U.S. Pat. No. 5,188,831, issued Feb. 23, 1993, describes sunscreen compositions wherein the sunscreen effect is obtained from a blended of oil-dispersible ultrafine titanium dioxide and water dispersible titanium dioxide. However, the SPF level obtained is only of 10 with a total concentration of titanium dioxide of 5.0% w/w.
World Patent Application WO 90/06103, published Jun. 14, 1990, describes titanium dioxide sunscreen where the microfine titanium dioxide particles are coated with a phospholipid, either through the use of a powder mill or through the making of a dispersion in an oil phase containing the phospholipid with a high shear mixer. The phospholipid coated titanium dioxide is the incorporated into sunscreen compositions. A high efficiency is claimed: the data presented shows SPF values of up to 11 for a 3.75% titanium dioxide concentration and up to 25 for a for a 7.5% concentration of titanium dioxide. The use of high shear mixer or a powder mill is complicated and energy intensive process.
EP 535372 A1, published Apr. 7, 1993 describes a method of preparing sunscreens in which a dispersion of zinc oxide and/or titanium dioxide particles in an oil are formed by milling.
EP 619999 A2, published Oct. 19, 1994 describes an aqueous dispersion of particulate metallic oxide of particle size less than 200 nm mixed with an emulsifier and an oil phase and also an organic hydrophobic sunscreen to form an o/w emulsion. The resulting sun protection composition has a higher SPF than would be expected if there was only an additive effect. However, the titanium dioxide alone at 4% yielded a SPF of only 7 to about 11.
EP 628303, published Oct. 19, 1994 describes a process for preparing a sunscreen composition. It consists of mixing sunscreen particles of metallic oxide less than 200 nm dispersed in an oil with one or more emulsifier and/or organic sunscreens. The resulting sunscreen composition is claimed to have a SPF value considerably higher than expected. The high SPF is only obtained when a metallic oxide is blended with an organic sunscreen. In fact, when no organic sunscreen is used, the SPF value is only about 7.
WO 93/11742 describes sunscreen compositions comprising titanium dioxide and iron oxide of particle size less than 200 nm preferably coated with a phospholipid.
An article published in DCI in September 1992 by Tioxide Specialties Ltd. Describes ways of incorporating oil or water dispersions of titanium dioxide in emulsions. However, no data is given on the resulting SPF values.
An article published in Cosmetics and Toiletries, Vol. 107, October 1992, describes various ways of formulating with a physical sunblock. The discussion focuses on using titanium dioxide in a dispersion or using an emulsifier which is also an effective dispersing agent for titanium dioxide. It states that SPF's far above 20 can be achieved. However, no examples are given, nor does the article mention the specific sunscreen components or their composition.
A brochure published by the Tioxide Company on Mar. 15, 1994, discloses inorganic sunscreens of high SPF values obtained without the addition of any organic sunscreens. When measured, the SPF of the sunscreen compositions was indeed that described. However, when the titanium dioxide concentration was measured, it was at least twice what was claimed.
U.S. Pat. No. 5,498,406 describes sunscreen compositions in an oil-in-water emulsion containing both organic and inorganic sunscreens and comprising long chain (C25-45) alcohols for stabilization of the emulsion. This composition relies predominately on the organic sunscreen actives. While the authors mention the use of stearic acid as a part of the oil in water composition, they teach against the use of stearic acid in stabilizing the titanium dioxide with C22-45 alcohols.
U.S. Pat. No. 6,099,825 describes sunscreen having disappearing color which is extremely useful when combined with titanium dioxide or zinc oxide. It was unexpectedly found that although the inclusion of particulate pigments in a sunscreen emulsion can render the sunscreen visually colored as it is being spread onto the skin and that the coloration will substantially disappear when the sunscreen emulsion is rubbed into the skin.
U.S. Pat. No. 6,042,813 also describes sunscreen having disappearing color indicator. The sunscreen includes at least one active sunscreen agent, at least one emulsifier, sufficient amounts of water to create the colored emulsion, and at least one oil-soluble dye that imparts color to the emulsion.
U.S. Pat. No. 6,048,517, issued Apr. 11, 2000, describes low-cost sunscreen compositions with high SPF values of at least 40. The ingredients in the sunscreen include mixtures of homosalate, octyl salicylate, oxybenzone, octyl methoxycinnamate, or avobenzone.
U.S. Pat. No. 5,770,183, issued Jun. 23, 1998, describes an emulsion that contains a water phase and an oil phase that includes active sunscreen ingredients and skin conditioning agents. The sunscreen provides an SPF greater than 30, and the particle size in the oil phase averages 2.0 Microns, providing high levels of protection from the sun while using minimum amounts of active sunscreen agents.
U.S. Pat. No. 5,492,690, issued Feb. 20, 1996, describes a method for preventing skin damage by applying a substance that includes a benzolyacetate ester and seems to describe a potential non-endocrine disrupting benzolyacetate ester that would require testing prior to use in the present inventive composition(s).
U.S. Pat. No. 5,747,010, issued May 5, 1998, describes means and methods of protecting skin from the oxidative effects of UVA radiation using a substance that contains a lipophilic anti-oxidant. Such an anti-oxidant, if proven to be non-endocrine disruptive and not to interfere with the cytoprotective qualities of the present inventive composition(s) could also be useful and beneficial.
WO 99/11236 published first in Germany and then as a WO document dated Mar. 11, 1999, describes a transparent sunscreen gel that contains methylvinyl ether and maleic acid copolymers cross-linked with decadiene.
EP 0834301, published Mar. 8, 1998, describes compositions that include glutathione liposomes combined with at least one emulsifier and are topically applied to the skin to prevent the damaging effects of UV radiation.
U.S. Pat. No. 5,914,102, issued Jun. 22, 1999, describes an oil-in-water sunscreen emulsion comprised of at least one ultraviolet-absorbing organic compound and hydrophobically-treated silica particles. The concentration of the organic compounds is at least 30 times the concentration of the silica.
U.S. Pat. No. 5,916,542, issued Jun. 29, 1999, describes a mixture comprised of natural substances that effectively protect against skin damage caused by UVA and UVB light.
U.S. Pat. No. 5,945,090, issued Aug. 31, 1999, describes a high-SPF sunscreen comprised of an algae extract, aloe vera, and tapioca powder that protects against UVA and UVB light.
U.S. Pat. No. 5,824,659 by Strickland and coworkers is that an extract found in all Aloe plants that is normally removed during carbon adsorptive processing, is capable of providing cytoprotection to the mammalian skin.
The present disclosure allows for no removal of these important constituents and the use of ZnO is not only a useful SPF inorganic sun-block agent but also a very useful inhibitor to ensure that the biological activity of the aloe barbadensis Miller in the composition of the present disclosure has a long shelf life without any biological “growth”. Shelf life is another important aspect of the present disclosure, in that many “all natural” or earth grown substances require (often toxic or endocrine disruptive) anti-bacterial substances to inhibit mold or other similar organisms from “growing” in the composition during the life of the product on the shelf.
U.S. Pat. No. 5,980,871, issued Nov. 9, 1999 to Johnson and Johnson, and apparently licensed to Neutrogena, describes a sunscreen composition that includes inorganic sunscreen agents, such as titanium dioxide or zinc oxide, anionic emulsifiers, and an oil component. The composition allows for SPF greater than 10 with a titanium dioxide concentration of about 4%. This U.S. Pat. No. 5,980,871 further describes the method required to make the sunscreen.
This disclosure does not describe the use of any cytoprotective agents or the importance of providing only non-endocrine disruptive agents to the composition. In fact the patented composition teaches away from the use of ingredients other than those that are “naturally derived” or “earth grown”. The product that is described in the '871 patent itself is also undesirable as it leaves a very white appearance on the skin for long periods of time, is difficult to spread, and somewhat abrasive to sensitive skin. In addition, the composition allows for the use of parabens as inactive ingredients, also recently found to be known endocrine disrupters.
In addition, the art with regard to testing for determining the concentration of endocrine disrupters has been reviewed and is summarized below:
Japanese Application No. 2001116753A2, published Apr. 27, 2001, describes a method to sensitively and simply detect an exogenous endocrine disruptor existing in environment with extremely low concentration.
Japanese Application No. 2002355079A2, published Dec. 10, 2002, describes a method for detecting a substance having the endocrine disruption actions by using the gene affected by the endocrine disruption actions and a DNA array or equivalents thereto used for the method for detecting the substance having the endocrine disruption actions.
Japanese Application No. 2003259895A2, published Sep. 16, 2003, describes an endocrine disruptor-measuring technique which uses as an indicator the change in the aromatase activity of a biosystem reflecting a state near to a living environment.
Japanese Application No. 2002365275A2, published Dec. 18, 2002, describes a diffusive gas concentration detection pipe bringing about measurement of better accuracy and higher sensitivity from a viewpoint of the subject related to a measure of an endocrine disrupter having become a problem in recent years.
U.S. Pat. Application No. 20030087324A1, published May 8, 2003, describes a method for immunologically detecting the endocrine disrupter or its degradation product and a method for immunologically concentrating the same each by using the above antibody.
WIPO Publication No. WO0026404A1, published May 11, 2000, describes a method for detecting a gene affected by an endocrine disruptor characterized by comprising preparing a nucleic acid sample containing mRNAs originating in cells, tissues or organisms, which have been brought into contact with a sample containing the endocrine disruptor, or cDNAs thereof; hybridizing the nucleic acid sample with DNA alleys wherein genes which might be affected by the endocrine disrupter or DNA fragments originating in these genes have been fixed; and then comparing the thus obtained results with the results obtained by using another nucleic acid sample originating in a comparative sample to thereby select the gene affected by the endocrine disruptor.